While many of us welcomed this recent warm spell, it’s also a reminder about a long-term weather trend that’s causing problems for Wisconsin’s loggers. As described in a UW-Madison news release earlier this winter, loggers can’t count on as many days of frozen ground as they used to, with a lot of negative consequences for the industry.
Here’s how the release starts:
Stable, frozen ground has long been recognized a logger’s friend, capable of supporting equipment and trucks in marshy or soggy forests. Now, a comprehensive look at weather from 1948 onward shows that the logger’s friend is melting.
The study, published in the current issue of the Journal of Environmental Management, finds that the period of frozen ground has declined by an average of two or three weeks since 1948. During that time, wood harvests have shifted in years with more variability in freezing and thawing to red pine and jack pine – species that grow in sandy, well-drained soil that can support trucks and heavy equipment when not frozen.
Jack pine, a characteristic north woods Wisconsin species, is declining, and areas that have been harvested are often replaced with a different species, changing the overall ecosystem.
The study was an effort to look at how long-term weather trends affect forestry, says author Adena Rissman, an assistant professor of forest and wildlife ecology at the University of Wisconsin-Madison. “When my co-author, Chad Rittenhouse, and I began this project, we wanted to know how weather affects our ability to support sustainable working forests. We found a significant decline in the duration of frozen ground over the past 65 years, and at the same time, a significant change in the species being harvested.”
Read more here.